What are some common sleep disorders?

At least 40 million Americans per year suffer from long-term sleep disorders. An additional 20 million experience occasional sleeping problems. Among the most common sleep disorders are insomnia, sleep apnea, restless legs syndrome, and narcolepsy.

Insomnia. At one time or another, nearly everyone experiences short-term insomnia, which can occur as a result of stress, diet, jet lag, or a number of other factors. Insomnia almost always affects job performance and a person's overall well-being. The condition increases with age and affects about 30% of men and 40% of women at some time.

For short-term cases of insomnia, health care providers may prescribe sleeping pills. Sleeping pills are generally not considered effective for long-term use because they stop working after several weeks of nightly use, and long-term use can interfere with sleep. For more serious or long-term cases of insomnia, researchers are examining other approaches, including the use of bright light (light therapy) to alter circadian rhythms.1

Sleep apnea. According to the National Sleep Foundation, approximately 18 million Americans have sleep apnea, but few of them have been diagnosed. Those with this condition experience pauses in their breathing while they are asleep. Physical changes, such as alterations in fat accumulation or loss of muscle tone with aging, can contribute to sleep apnea. Typical features of this disorder include loud snoring, obesity, and excessive daytime sleepiness. Although sleep apnea is associated with loud snoring, not all people who snore have sleep apnea.

Diagnosing sleep apnea requires monitoring people while they are sleeping and recording measurements of some of their body functions and activities during sleep. A polysomnogram (pronounced pol-ee-SOM-nuh-gram) is a record of a person's sleep pattern, breathing, and heart activity. A polysomnogram is produced by a sleep test, called polysomnography, which can diagnose sleep apnea. This test records a person's brain waves, heartbeat, and breathing during an entire night, allowing for a diagnosis of sleep apnea. Methods of treating sleep apnea include losing weight and preventing a person from sleeping on his or her back. Another option is a special device or surgery to correct the obstruction in the airway. People with sleep apnea should not take sedatives or sleeping pills because these medications can prevent them from waking up to breathe.1

Restless legs syndrome (RLS). According to the National Institute of Neurological Disorders and Stroke, as many as 10% of Americans may have RLS.1 This condition tends to run in families and causes unpleasant sensations of crawling, prickling, or tingling in the legs and feet, with a resulting need to move the feet and legs for relief. People with RLS may move their legs constantly during the day and night, which can result in trouble sleeping.

Symptoms of RLS can occur at any age, but the most severe cases usually occur in the elderly. Many RLS patients have a disorder called periodic limb movement disorder (PLMD), which causes repetitive jerking movements of the limbs, particularly the legs. The movements occur every 20 to 40 seconds and can cause awakening throughout the night. Treatments prescribed for RLS and PLMD include drugs that affect dopamine, a neurotransmitter. However, because RLS and PLMD are not well understood, the reasons that drugs affecting the levels of dopamine in the brain are useful are also not well understood.1

Narcolepsy. Approximately 0.02% to 0.067% of Americans are affected by narcolepsy.2 People with this condition experience "sleep attacks" throughout the day even though they may have had adequate sleep during the previous night. The sleep attacks last from several seconds to 30 minutes or more. In addition to falling asleep at unexpected times, people with narcolepsy may have loss of muscle control during emotional situations, hallucinations, temporary paralysis, and disrupted nighttime sleep. Narcolepsy tends to run in families with a history of sleep disorders, and it also occurs in some people who have experienced head trauma or injury.

Once diagnosed, narcolepsy can be treated with drugs that control its symptoms. Commonly prescribed drugs for this condition include stimulants and antidepressants. Because each case is different, the drug that is most effective depends on the person.